Network services—including messaging systems, blogging services, discussion boards, and social network services—permit users to identify one another and share multiple types of information with one another. Users of these services may establish profiles that include information about the users' identity and interests, and other users may view this information or receive notifications when the information changes. Users may also send messages to one another, such as by sending private messages, sending multicast messages, and sending broadcast messages. Some network services enable users to share information about their past, present, or future interests and activities, and allow other users to receive notifications about these interests and activities. Further, pictures, audio, videos, web content, and other types of information may be shared between users. Sending such messages and sharing such information between users is done actively, by a user designating other users to receive some information, or passively, such as by posting messages and information in a publicly-accessible location or in a location accessible to other users with which the user has a connection.
To receive such information, users of network services establish links or connections to one another that indicate an offline relationship between the users. For example, a connection may be created between family members, friends, or co-workers. Additionally, a connection may be created between people without an existing offline relationship, such as between a user and another that the user has identified in the network service. When users are connected in this way, the network service may make available to the users information that has been actively or passively shared between users (e.g., explicitly broadcast or posted in an accessible location).
Network services such as these include services like Facebook®, Twitter®, Microsoft® Mingle, and Google® Reader, which permit users to share information with “friends” (in) Facebook® and “followers” (in Twitter® and Google® Reader).
Other ways exist in which people may share information and exchange content. For example, people may publish information they release online (e.g., blog entries, photos, etc.) or distribute notifications regarding the information via a feed protocol like the Really Simple Syndication (RSS) protocol or the Atom Publishing Protocol (Atom). Other people may then download and view entries in the feed using a feed reader.
Some services exist that manipulate information available via network services, feed readers, and other web distribution tools. These tools operate to filter or reorganize the available information based on explicit user input. For example, the TwitterTim.es service allows a user to establish particular “channels” from his or her Twitter feed that each filter the Twitter content that fits the parameters of those channels.